AP Psychology

1. AP Psychology 2.1 Nervous System / Endocrine System and Behavior

2. I. Neural Communication Neuron • Building block of NS / uses chemical and electrical signals • Components • Cell body / soma – contains nucleus; receives message from dendrites • Dendrites – receive and communicate signals from neuron to cell body • Axon – conduit that communicate signal down the neuron away from cell body

3. I. Neural Communication 2. Components cont. D. Myelin Sheath – insulation around Schwanncells that stop leaking of signals (formed by glial cells), increases velocity of transmission ** MS (multiple sclerosis) is caused by deterioration of myelin sheath which results in loss of controlling muscle movement

4. I. Neural Communication E. Schwann Cell – chain of cells around axon F. Nodes of Ranvier – space between Schwann Cells G. Axon Terminals – contain synaptic vesciles that contain neurotransmitters

7. I. Neural Communication Action Potential • Brief electrical impulse / info transmitted • All neurons have charge • Resting Potential – sodium and potassium channels closed -70mV • Depolarization – sodium channels open and flood inside / potassium channels closed • Action Potential – if depolarization reached threshold, an action potential will be created and it will fire (all-or-none law) • Saltatory conduction – chemical signal down the neuron from one node to the next • Repolarization and hyperpolarization – decrease in potential because potassium leaves cell, sodium channels close (goes from positive to negative potential)

9. I. Neural Communication Passage of a nerve to a reflex action • Synapse – gap between nerve cells or nerve cells and muscles • Synaptic vesicle – small membrane that releases neurotransmitters into the synapse

10. I. Neural Communication Neurotransmitters • Chemical messengers manufactured by neuron • Hundreds • Endorphins – best-known / reduce pain or produce feelings of pleasure (“runner’s high” – boosted mood) • Play a role in eating habits and body weight (when levels of norepinephrine, dopamine, serotonin, leptin and othes are low, hunger and or eating results…when levels are high, satiety (fullness) results • Play a role in influencing or causing eating disorders

11. Neurotransmitters – AP MC ?’s Neurotransmitter / function Disease associated with *Parkinson’s (too little) / *Schizophrenia (too much) 2. Depression, Anxiety, OCD High blood pressure, Anxiety *Alzheimer’s, Muscular disorders Anxiety Opiate addiction (painkillers) • *Dopamine – movement / thought process • Serotonin – emotional state / sleep • Norepinephrine – physical arousal / learning, memory • *Acetylcholine – learning, memory, muscle contact • GABA – inhibition of brain activity • Endorphins – natural pain killers

12. I. Neural Communication Sensory (Afferent)- respond to touch, sound, light and numerous other stimuli affecting cells of the sensory organs that then send signals to the spinal cord and brain Motor (Efferent)- receive signals from the brain and spinal cord, cause muscle contractions, and affect glands Interneuron - connect neurons to other neurons within the same region of the brain or spinal cord.

14. I. Neural Communication Drug Effects on Nervous System • Psychoactive drugs have inhibitory or excitatory effects • Agonists are drugs that mimic neurotransmitters • Antagonists are drugs that inhibit the effect of a neurotransmitter • Prozac is an antidepressant that works as an agonist of serotonin • Many psychoactive drugs have side effects because the drug of choice may work on different neural pathways • Example – Prozac treats depression, but can alter sleep, eating patterns and other thought processes

16. II. Nervous System Central NS (CNS) • Brain and spinal cord (command center of body) • Spinal cord deals with reflex or involuntary actions • Injuries to result in paralysis of limbs / higher the damage the more severe the injury • “knee-jerk” reflex – used by doctors for neurological exam • Brain is required for voluntary movements

19. II. Nervous System Peripheral NS (PNS) • Connects the CNS with the rest of the body through nerves • Carries incoming messages to your brain (afferent) and outgoing signals to muscles and glands (efferent) • Ex…as you cross a traffic-filled street, your PNS will notice the auditory sounds of cars and the visual patterns of oncoming traffic. Your brain assesses the situation and tells your body that danger may be lingering, so you cross the street with caution

21. II. Nervous System Somatic NS of the PNS • Allows communication with the outside world / consciously aware • Carries info to CNS and sends voluntary signals to your muscles / sensations we are aware of (pain, sound, light) • Ex…you smell food, your muscles are induced to eat the food

24. II. Nervous System Autonomic NS of the PNS • Carries info to the CNS and sends voluntary signals to your muscles • Regulates digestion, respiration, sleep and other vital functions

26. II. Nervous System Divisions of the ANS • Sympathetic NS • responsible for arousing the body and mobilizing its energy during times of stress • Increase respiratory and heart rates, dilation of pupils • “Fight or flight” response allows you to attack or flee • Parasympathetic NS • Allows a person to return to a calm and collected state after arousal

31. III. Endocrine System • System of hormones that carry messages through different glands • Major glands and tissues • Hypothalamus – links the nervous and endocrine systems / located in lower half of brain / also allows humans to sense thirst and hunger • Pituitary Gland – “master gland” (regulates activity of other glands) / under control of the hypothalamus • Thyroid Gland – located near the trachea (metabolism) • Parathyroid Gland – located on the surface of thyroid

33. III. Endocrine System • Pancreas – located near kidneys / contain special cells called Islets of Langerhans that secrete hormones • Adrenal Glands – located on top of kidneys / in an emergency they release hormones that cause increase in heart rate, blood pressure, sugar levels while reducing blood flow to digestive system • Gonads – testes and ovaries • Pineal Gland – small peanut-shaped gland near the center of the brain

34. III. Endocrine System Gland Hormone Action • Pituitary Oxytocin contraction of uterus; breast milk • Pituitary Growth hormone stimulates growth • Pituitary Prolactin stimulate milk production • Pituitary Follicle Stimulating stimulates sperm • Pituitary Luteinizing stimulates ovaries • Pituitary Thyroid Stimulating stimulates thyroid • Thyroid Triiodothyronine/thyroxine metabolism • Thyroid Calcitonin stimulates bone construction • Parathyroid Parathyroid raises blood calcium • Pancreas Insulin lowers blood glucose • Pancreas Glucagon raise blood glucose • Adrenal Norepinephrine/epinephrine “fight-or-flight”, metabolism • Testes Androgens sperm formation/secondary male • Ovaries Estrogen s stimulates uterine lining/secondary female • Ovaries Progesterone maintains pregnancy • Pineal Melatonin sleep-wake cycle/circadian rhythms

35. IV. Brain Tools for brain research: 1. EEG (electroencephalogram) • Electrical activity throughout the brain sweep in waves • records these wave patterns • reveals areas that are most active during a particular task or change in mental state • Can trace abnormal brain waves caused by brain malfunctions (ie...epilepsy)

37. IV. Brain Tools for brain research: 2. PET Scan (Positron Emission Topography) • Harmless radioactive glucose injected into bloodstream • Color-coded images • Originally designed for abnormalities, now used to identify areas active during ordinary activities

39. IV. Brain CT Scan (Computerized Tomography) • X-rays / least expensive • Reveal effects of strokes, tumors and other brain disorders

40. IV. Brain 4. MRI (Magnetic Resonance Imaging) • Uses a high-frequency magnetic field to produce detailed, high-resolution pictures • Map brain structures and identify abnormalities

42. IV. Brain Hindbrain • Oldest part of the brain to develop in evolutionary terms / controls autonomic behaviors (respiration and heartbeat) • Medulla – controls vital life functions (breathing, circulation, swallowing) • Pons – Latin for bridge / responsible for sleeping, walking, dreaming • Cerebellum – coordinating fine muscle movement, maintaining posture, equilibrium

44. IV. Brain Midbrain • Integrates auditory and visual sensory information and muscle movements • Reticular Formation – network of nerve fibers that run through the center of the midbrain • Regulates attention, arousal, and sleep • Without this you would not be alert or even conscious

46. IV. Brain Forebrain • Largest and most complex region / center for complex behaviors and mental processes • Thalamus – brain’s relay station (receives input from all senses – except smell – and directs info to appropriate area) • Injury to can cause blindness / deafness • Associated with Schizophrenia • Hypothalamus – located under thalamus (hypo – Latin for below) size of peanut • Brain’s “master control center” – regulates hunger and thirst (satiety) • Damage to can increase eating or produce feelings of fullness

48. IV. Brain Forebrain cont. • Hippocampus – forming new memories of events and info • Amygdala – production and regulation of emotions (aggression, fear, disgust) • Limbic System – made of hippocampus, amygdala and hypothalamus / plays a key role in the experience of emotions • Cerebral Cortex – cortex means bark / thin outer covering (1/4”) of the forebrain • gray, wrinkled (convolutions) / 30 billion neurons / 270 billion glial cells • Two hemispheres – control opposite side of body

50. IV. Brain Left Hemisphere Right Hemisphere Nonverbal (visual recognition and music) Negative emotions Response to commands Memory for shapes Memory for music Understanding spatial relationships Understanding images • Verbal / Analytical • Positive emotions • Muscles for speech • Movements • Spontaneity • Memory for words and numbers • Understanding speech and writing